xref: /linux/drivers/input/evdev.c (revision 2624f124b3b5d550ab2fbef7ee3bc0e1fed09722)
1 /*
2  * Event char devices, giving access to raw input device events.
3  *
4  * Copyright (c) 1999-2002 Vojtech Pavlik
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published by
8  * the Free Software Foundation.
9  */
10 
11 #define EVDEV_MINOR_BASE	64
12 #define EVDEV_MINORS		32
13 #define EVDEV_BUFFER_SIZE	64
14 
15 #include <linux/poll.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/input.h>
20 #include <linux/major.h>
21 #include <linux/smp_lock.h>
22 #include <linux/device.h>
23 #include <linux/devfs_fs_kernel.h>
24 #include <linux/compat.h>
25 
26 struct evdev {
27 	int exist;
28 	int open;
29 	int minor;
30 	char name[16];
31 	struct input_handle handle;
32 	wait_queue_head_t wait;
33 	struct evdev_list *grab;
34 	struct list_head list;
35 };
36 
37 struct evdev_list {
38 	struct input_event buffer[EVDEV_BUFFER_SIZE];
39 	int head;
40 	int tail;
41 	struct fasync_struct *fasync;
42 	struct evdev *evdev;
43 	struct list_head node;
44 };
45 
46 static struct evdev *evdev_table[EVDEV_MINORS];
47 
48 static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
49 {
50 	struct evdev *evdev = handle->private;
51 	struct evdev_list *list;
52 
53 	if (evdev->grab) {
54 		list = evdev->grab;
55 
56 		do_gettimeofday(&list->buffer[list->head].time);
57 		list->buffer[list->head].type = type;
58 		list->buffer[list->head].code = code;
59 		list->buffer[list->head].value = value;
60 		list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1);
61 
62 		kill_fasync(&list->fasync, SIGIO, POLL_IN);
63 	} else
64 		list_for_each_entry(list, &evdev->list, node) {
65 
66 			do_gettimeofday(&list->buffer[list->head].time);
67 			list->buffer[list->head].type = type;
68 			list->buffer[list->head].code = code;
69 			list->buffer[list->head].value = value;
70 			list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1);
71 
72 			kill_fasync(&list->fasync, SIGIO, POLL_IN);
73 		}
74 
75 	wake_up_interruptible(&evdev->wait);
76 }
77 
78 static int evdev_fasync(int fd, struct file *file, int on)
79 {
80 	int retval;
81 	struct evdev_list *list = file->private_data;
82 	retval = fasync_helper(fd, file, on, &list->fasync);
83 	return retval < 0 ? retval : 0;
84 }
85 
86 static int evdev_flush(struct file * file)
87 {
88 	struct evdev_list *list = file->private_data;
89 	if (!list->evdev->exist) return -ENODEV;
90 	return input_flush_device(&list->evdev->handle, file);
91 }
92 
93 static void evdev_free(struct evdev *evdev)
94 {
95 	evdev_table[evdev->minor] = NULL;
96 	kfree(evdev);
97 }
98 
99 static int evdev_release(struct inode * inode, struct file * file)
100 {
101 	struct evdev_list *list = file->private_data;
102 
103 	if (list->evdev->grab == list) {
104 		input_release_device(&list->evdev->handle);
105 		list->evdev->grab = NULL;
106 	}
107 
108 	evdev_fasync(-1, file, 0);
109 	list_del(&list->node);
110 
111 	if (!--list->evdev->open) {
112 		if (list->evdev->exist)
113 			input_close_device(&list->evdev->handle);
114 		else
115 			evdev_free(list->evdev);
116 	}
117 
118 	kfree(list);
119 	return 0;
120 }
121 
122 static int evdev_open(struct inode * inode, struct file * file)
123 {
124 	struct evdev_list *list;
125 	int i = iminor(inode) - EVDEV_MINOR_BASE;
126 	int accept_err;
127 
128 	if (i >= EVDEV_MINORS || !evdev_table[i] || !evdev_table[i]->exist)
129 		return -ENODEV;
130 
131 	if ((accept_err = input_accept_process(&(evdev_table[i]->handle), file)))
132 		return accept_err;
133 
134 	if (!(list = kmalloc(sizeof(struct evdev_list), GFP_KERNEL)))
135 		return -ENOMEM;
136 	memset(list, 0, sizeof(struct evdev_list));
137 
138 	list->evdev = evdev_table[i];
139 	list_add_tail(&list->node, &evdev_table[i]->list);
140 	file->private_data = list;
141 
142 	if (!list->evdev->open++)
143 		if (list->evdev->exist)
144 			input_open_device(&list->evdev->handle);
145 
146 	return 0;
147 }
148 
149 #ifdef CONFIG_COMPAT
150 struct input_event_compat {
151 	struct compat_timeval time;
152 	__u16 type;
153 	__u16 code;
154 	__s32 value;
155 };
156 
157 #ifdef CONFIG_X86_64
158 #  define COMPAT_TEST test_thread_flag(TIF_IA32)
159 #elif defined(CONFIG_IA64)
160 #  define COMPAT_TEST IS_IA32_PROCESS(ia64_task_regs(current))
161 #elif defined(CONFIG_ARCH_S390)
162 #  define COMPAT_TEST test_thread_flag(TIF_31BIT)
163 #elif defined(CONFIG_MIPS)
164 #  define COMPAT_TEST (current->thread.mflags & MF_32BIT_ADDR)
165 #else
166 #  define COMPAT_TEST test_thread_flag(TIF_32BIT)
167 #endif
168 
169 static ssize_t evdev_write_compat(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
170 {
171 	struct evdev_list *list = file->private_data;
172 	struct input_event_compat event;
173 	int retval = 0;
174 
175 	while (retval < count) {
176 		if (copy_from_user(&event, buffer + retval, sizeof(struct input_event_compat)))
177 			return -EFAULT;
178 		input_event(list->evdev->handle.dev, event.type, event.code, event.value);
179 		retval += sizeof(struct input_event_compat);
180 	}
181 
182 	return retval;
183 }
184 #endif
185 
186 static ssize_t evdev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
187 {
188 	struct evdev_list *list = file->private_data;
189 	struct input_event event;
190 	int retval = 0;
191 
192 	if (!list->evdev->exist) return -ENODEV;
193 
194 #ifdef CONFIG_COMPAT
195 	if (COMPAT_TEST)
196 		return evdev_write_compat(file, buffer, count, ppos);
197 #endif
198 
199 	while (retval < count) {
200 
201 		if (copy_from_user(&event, buffer + retval, sizeof(struct input_event)))
202 			return -EFAULT;
203 		input_event(list->evdev->handle.dev, event.type, event.code, event.value);
204 		retval += sizeof(struct input_event);
205 	}
206 
207 	return retval;
208 }
209 
210 #ifdef CONFIG_COMPAT
211 static ssize_t evdev_read_compat(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
212 {
213 	struct evdev_list *list = file->private_data;
214 	int retval;
215 
216 	if (count < sizeof(struct input_event_compat))
217 		return -EINVAL;
218 
219 	if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK))
220 		return -EAGAIN;
221 
222 	retval = wait_event_interruptible(list->evdev->wait,
223 		list->head != list->tail || (!list->evdev->exist));
224 
225 	if (retval)
226 		return retval;
227 
228 	if (!list->evdev->exist)
229 		return -ENODEV;
230 
231 	while (list->head != list->tail && retval + sizeof(struct input_event_compat) <= count) {
232 		struct input_event *event = (struct input_event *) list->buffer + list->tail;
233 		struct input_event_compat event_compat;
234 		event_compat.time.tv_sec = event->time.tv_sec;
235 		event_compat.time.tv_usec = event->time.tv_usec;
236 		event_compat.type = event->type;
237 		event_compat.code = event->code;
238 		event_compat.value = event->value;
239 
240 		if (copy_to_user(buffer + retval, &event_compat,
241 			sizeof(struct input_event_compat))) return -EFAULT;
242 		list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
243 		retval += sizeof(struct input_event_compat);
244 	}
245 
246 	return retval;
247 }
248 #endif
249 
250 static ssize_t evdev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
251 {
252 	struct evdev_list *list = file->private_data;
253 	int retval;
254 
255 #ifdef CONFIG_COMPAT
256 	if (COMPAT_TEST)
257 		return evdev_read_compat(file, buffer, count, ppos);
258 #endif
259 
260 	if (count < sizeof(struct input_event))
261 		return -EINVAL;
262 
263 	if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK))
264 		return -EAGAIN;
265 
266 	retval = wait_event_interruptible(list->evdev->wait,
267 		list->head != list->tail || (!list->evdev->exist));
268 
269 	if (retval)
270 		return retval;
271 
272 	if (!list->evdev->exist)
273 		return -ENODEV;
274 
275 	while (list->head != list->tail && retval + sizeof(struct input_event) <= count) {
276 		if (copy_to_user(buffer + retval, list->buffer + list->tail,
277 			sizeof(struct input_event))) return -EFAULT;
278 		list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
279 		retval += sizeof(struct input_event);
280 	}
281 
282 	return retval;
283 }
284 
285 /* No kernel lock - fine */
286 static unsigned int evdev_poll(struct file *file, poll_table *wait)
287 {
288 	struct evdev_list *list = file->private_data;
289 	poll_wait(file, &list->evdev->wait, wait);
290 	return ((list->head == list->tail) ? 0 : (POLLIN | POLLRDNORM)) |
291 		(list->evdev->exist ? 0 : (POLLHUP | POLLERR));
292 }
293 
294 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
295 {
296 	struct evdev_list *list = file->private_data;
297 	struct evdev *evdev = list->evdev;
298 	struct input_dev *dev = evdev->handle.dev;
299 	struct input_absinfo abs;
300 	void __user *p = (void __user *)arg;
301 	int __user *ip = (int __user *)arg;
302 	int i, t, u, v;
303 
304 	if (!evdev->exist) return -ENODEV;
305 
306 	switch (cmd) {
307 
308 		case EVIOCGVERSION:
309 			return put_user(EV_VERSION, ip);
310 
311 		case EVIOCGID:
312 			return copy_to_user(p, &dev->id, sizeof(struct input_id)) ? -EFAULT : 0;
313 
314 		case EVIOCGKEYCODE:
315 			if (get_user(t, ip)) return -EFAULT;
316 			if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL;
317 			if (put_user(INPUT_KEYCODE(dev, t), ip + 1)) return -EFAULT;
318 			return 0;
319 
320 		case EVIOCSKEYCODE:
321 			if (get_user(t, ip)) return -EFAULT;
322 			if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL;
323 			if (get_user(v, ip + 1)) return -EFAULT;
324 			if (v < 0 || v > KEY_MAX) return -EINVAL;
325 			if (v >> (dev->keycodesize * 8)) return -EINVAL;
326 			u = SET_INPUT_KEYCODE(dev, t, v);
327 			clear_bit(u, dev->keybit);
328 			set_bit(v, dev->keybit);
329 			for (i = 0; i < dev->keycodemax; i++)
330 				if (INPUT_KEYCODE(dev,i) == u)
331 					set_bit(u, dev->keybit);
332 			return 0;
333 
334 		case EVIOCSFF:
335 			if (dev->upload_effect) {
336 				struct ff_effect effect;
337 				int err;
338 
339 				if (copy_from_user(&effect, p, sizeof(effect)))
340 					return -EFAULT;
341 				err = dev->upload_effect(dev, &effect);
342 				if (put_user(effect.id, &(((struct ff_effect __user *)arg)->id)))
343 					return -EFAULT;
344 				return err;
345 			}
346 			else return -ENOSYS;
347 
348 		case EVIOCRMFF:
349 			if (dev->erase_effect) {
350 				return dev->erase_effect(dev, (int)arg);
351 			}
352 			else return -ENOSYS;
353 
354 		case EVIOCGEFFECTS:
355 			if (put_user(dev->ff_effects_max, ip))
356 				return -EFAULT;
357 			return 0;
358 
359 		case EVIOCGRAB:
360 			if (arg) {
361 				if (evdev->grab)
362 					return -EBUSY;
363 				if (input_grab_device(&evdev->handle))
364 					return -EBUSY;
365 				evdev->grab = list;
366 				return 0;
367 			} else {
368 				if (evdev->grab != list)
369 					return -EINVAL;
370 				input_release_device(&evdev->handle);
371 				evdev->grab = NULL;
372 				return 0;
373 			}
374 
375 		default:
376 
377 			if (_IOC_TYPE(cmd) != 'E')
378 				return -EINVAL;
379 
380 			if (_IOC_DIR(cmd) == _IOC_READ) {
381 
382 				if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
383 
384 					long *bits;
385 					int len;
386 
387 					switch (_IOC_NR(cmd) & EV_MAX) {
388 						case      0: bits = dev->evbit;  len = EV_MAX;  break;
389 						case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
390 						case EV_REL: bits = dev->relbit; len = REL_MAX; break;
391 						case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
392 						case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
393 						case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
394 						case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
395 						case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
396 						case EV_SW:  bits = dev->swbit;  len = SW_MAX;  break;
397 						default: return -EINVAL;
398 					}
399 					len = NBITS(len) * sizeof(long);
400 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
401 					return copy_to_user(p, bits, len) ? -EFAULT : len;
402 				}
403 
404 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) {
405 					int len;
406 					len = NBITS(KEY_MAX) * sizeof(long);
407 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
408 					return copy_to_user(p, dev->key, len) ? -EFAULT : len;
409 				}
410 
411 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) {
412 					int len;
413 					len = NBITS(LED_MAX) * sizeof(long);
414 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
415 					return copy_to_user(p, dev->led, len) ? -EFAULT : len;
416 				}
417 
418 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) {
419 					int len;
420 					len = NBITS(SND_MAX) * sizeof(long);
421 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
422 					return copy_to_user(p, dev->snd, len) ? -EFAULT : len;
423 				}
424 
425 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0))) {
426 					int len;
427 					len = NBITS(SW_MAX) * sizeof(long);
428 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
429 					return copy_to_user(p, dev->sw, len) ? -EFAULT : len;
430 				}
431 
432 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) {
433 					int len;
434 					if (!dev->name) return -ENOENT;
435 					len = strlen(dev->name) + 1;
436 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
437 					return copy_to_user(p, dev->name, len) ? -EFAULT : len;
438 				}
439 
440 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) {
441 					int len;
442 					if (!dev->phys) return -ENOENT;
443 					len = strlen(dev->phys) + 1;
444 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
445 					return copy_to_user(p, dev->phys, len) ? -EFAULT : len;
446 				}
447 
448 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) {
449 					int len;
450 					if (!dev->uniq) return -ENOENT;
451 					len = strlen(dev->uniq) + 1;
452 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
453 					return copy_to_user(p, dev->uniq, len) ? -EFAULT : len;
454 				}
455 
456 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
457 
458 					int t = _IOC_NR(cmd) & ABS_MAX;
459 
460 					abs.value = dev->abs[t];
461 					abs.minimum = dev->absmin[t];
462 					abs.maximum = dev->absmax[t];
463 					abs.fuzz = dev->absfuzz[t];
464 					abs.flat = dev->absflat[t];
465 
466 					if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
467 						return -EFAULT;
468 
469 					return 0;
470 				}
471 
472 			}
473 
474 			if (_IOC_DIR(cmd) == _IOC_WRITE) {
475 
476 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
477 
478 					int t = _IOC_NR(cmd) & ABS_MAX;
479 
480 					if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
481 						return -EFAULT;
482 
483 					dev->abs[t] = abs.value;
484 					dev->absmin[t] = abs.minimum;
485 					dev->absmax[t] = abs.maximum;
486 					dev->absfuzz[t] = abs.fuzz;
487 					dev->absflat[t] = abs.flat;
488 
489 					return 0;
490 				}
491 			}
492 	}
493 	return -EINVAL;
494 }
495 
496 #ifdef CONFIG_COMPAT
497 
498 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
499 #define NBITS_COMPAT(x) ((((x)-1)/BITS_PER_LONG_COMPAT)+1)
500 #define OFF_COMPAT(x)  ((x)%BITS_PER_LONG_COMPAT)
501 #define BIT_COMPAT(x)  (1UL<<OFF_COMPAT(x))
502 #define LONG_COMPAT(x) ((x)/BITS_PER_LONG_COMPAT)
503 #define test_bit_compat(bit, array) ((array[LONG_COMPAT(bit)] >> OFF_COMPAT(bit)) & 1)
504 
505 #ifdef __BIG_ENDIAN
506 #define bit_to_user(bit, max) \
507 do { \
508 	int i; \
509 	int len = NBITS_COMPAT((max)) * sizeof(compat_long_t); \
510 	if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); \
511 	for (i = 0; i < len / sizeof(compat_long_t); i++) \
512 		if (copy_to_user((compat_long_t*) p + i, \
513 				 (compat_long_t*) (bit) + i + 1 - ((i % 2) << 1), \
514 				 sizeof(compat_long_t))) \
515 			return -EFAULT; \
516 	return len; \
517 } while (0)
518 #else
519 #define bit_to_user(bit, max) \
520 do { \
521 	int len = NBITS_COMPAT((max)) * sizeof(compat_long_t); \
522 	if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); \
523 	return copy_to_user(p, (bit), len) ? -EFAULT : len; \
524 } while (0)
525 #endif
526 
527 static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
528 {
529 	struct evdev_list *list = file->private_data;
530 	struct evdev *evdev = list->evdev;
531 	struct input_dev *dev = evdev->handle.dev;
532 	struct input_absinfo abs;
533 	void __user *p = compat_ptr(arg);
534 
535 	if (!evdev->exist) return -ENODEV;
536 
537 	switch (cmd) {
538 
539 		case EVIOCGVERSION:
540 		case EVIOCGID:
541 		case EVIOCGKEYCODE:
542 		case EVIOCSKEYCODE:
543 		case EVIOCSFF:
544 		case EVIOCRMFF:
545 		case EVIOCGEFFECTS:
546 		case EVIOCGRAB:
547 			return evdev_ioctl(file, cmd, (unsigned long) p);
548 
549 		default:
550 
551 			if (_IOC_TYPE(cmd) != 'E')
552 				return -EINVAL;
553 
554 			if (_IOC_DIR(cmd) == _IOC_READ) {
555 
556 				if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
557 					long *bits;
558 					int max;
559 
560 					switch (_IOC_NR(cmd) & EV_MAX) {
561 						case      0: bits = dev->evbit;  max = EV_MAX;  break;
562 						case EV_KEY: bits = dev->keybit; max = KEY_MAX; break;
563 						case EV_REL: bits = dev->relbit; max = REL_MAX; break;
564 						case EV_ABS: bits = dev->absbit; max = ABS_MAX; break;
565 						case EV_MSC: bits = dev->mscbit; max = MSC_MAX; break;
566 						case EV_LED: bits = dev->ledbit; max = LED_MAX; break;
567 						case EV_SND: bits = dev->sndbit; max = SND_MAX; break;
568 						case EV_FF:  bits = dev->ffbit;  max = FF_MAX;  break;
569 						default: return -EINVAL;
570 					}
571 					bit_to_user(bits, max);
572 				}
573 
574 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
575 					bit_to_user(dev->key, KEY_MAX);
576 
577 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
578 					bit_to_user(dev->led, LED_MAX);
579 
580 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
581 					bit_to_user(dev->snd, SND_MAX);
582 
583 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) {
584 					int len;
585 					if (!dev->name) return -ENOENT;
586 					len = strlen(dev->name) + 1;
587 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
588 					return copy_to_user(p, dev->name, len) ? -EFAULT : len;
589 				}
590 
591 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) {
592 					int len;
593 					if (!dev->phys) return -ENOENT;
594 					len = strlen(dev->phys) + 1;
595 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
596 					return copy_to_user(p, dev->phys, len) ? -EFAULT : len;
597 				}
598 
599 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) {
600 					int len;
601 					if (!dev->uniq) return -ENOENT;
602 					len = strlen(dev->uniq) + 1;
603 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
604 					return copy_to_user(p, dev->uniq, len) ? -EFAULT : len;
605 				}
606 
607 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
608 
609 					int t = _IOC_NR(cmd) & ABS_MAX;
610 
611 					abs.value = dev->abs[t];
612 					abs.minimum = dev->absmin[t];
613 					abs.maximum = dev->absmax[t];
614 					abs.fuzz = dev->absfuzz[t];
615 					abs.flat = dev->absflat[t];
616 
617 					if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
618 						return -EFAULT;
619 
620 					return 0;
621 				}
622 			}
623 
624 			if (_IOC_DIR(cmd) == _IOC_WRITE) {
625 
626 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
627 
628 					int t = _IOC_NR(cmd) & ABS_MAX;
629 
630 					if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
631 						return -EFAULT;
632 
633 					dev->abs[t] = abs.value;
634 					dev->absmin[t] = abs.minimum;
635 					dev->absmax[t] = abs.maximum;
636 					dev->absfuzz[t] = abs.fuzz;
637 					dev->absflat[t] = abs.flat;
638 
639 					return 0;
640 				}
641 			}
642 	}
643 	return -EINVAL;
644 }
645 #endif
646 
647 static struct file_operations evdev_fops = {
648 	.owner =	THIS_MODULE,
649 	.read =		evdev_read,
650 	.write =	evdev_write,
651 	.poll =		evdev_poll,
652 	.open =		evdev_open,
653 	.release =	evdev_release,
654 	.unlocked_ioctl = evdev_ioctl,
655 #ifdef CONFIG_COMPAT
656 	.compat_ioctl =	evdev_ioctl_compat,
657 #endif
658 	.fasync =	evdev_fasync,
659 	.flush =	evdev_flush
660 };
661 
662 static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id)
663 {
664 	struct evdev *evdev;
665 	int minor;
666 
667 	for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
668 	if (minor == EVDEV_MINORS) {
669 		printk(KERN_ERR "evdev: no more free evdev devices\n");
670 		return NULL;
671 	}
672 
673 	if (!(evdev = kmalloc(sizeof(struct evdev), GFP_KERNEL)))
674 		return NULL;
675 	memset(evdev, 0, sizeof(struct evdev));
676 
677 	INIT_LIST_HEAD(&evdev->list);
678 	init_waitqueue_head(&evdev->wait);
679 
680 	evdev->exist = 1;
681 	evdev->minor = minor;
682 	evdev->handle.dev = dev;
683 	evdev->handle.name = evdev->name;
684 	evdev->handle.handler = handler;
685 	evdev->handle.private = evdev;
686 	sprintf(evdev->name, "event%d", minor);
687 
688 	evdev_table[minor] = evdev;
689 
690 	devfs_mk_cdev(MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
691 			S_IFCHR|S_IRUGO|S_IWUSR, "input/event%d", minor);
692 	class_device_create(input_class,
693 			MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
694 			dev->dev, "event%d", minor);
695 
696 	return &evdev->handle;
697 }
698 
699 static void evdev_disconnect(struct input_handle *handle)
700 {
701 	struct evdev *evdev = handle->private;
702 	struct evdev_list *list;
703 
704 	class_device_destroy(input_class,
705 			MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor));
706 	devfs_remove("input/event%d", evdev->minor);
707 	evdev->exist = 0;
708 
709 	if (evdev->open) {
710 		input_close_device(handle);
711 		wake_up_interruptible(&evdev->wait);
712 		list_for_each_entry(list, &evdev->list, node)
713 			kill_fasync(&list->fasync, SIGIO, POLL_HUP);
714 	} else
715 		evdev_free(evdev);
716 }
717 
718 static struct input_device_id evdev_ids[] = {
719 	{ .driver_info = 1 },	/* Matches all devices */
720 	{ },			/* Terminating zero entry */
721 };
722 
723 MODULE_DEVICE_TABLE(input, evdev_ids);
724 
725 static struct input_handler evdev_handler = {
726 	.event =	evdev_event,
727 	.connect =	evdev_connect,
728 	.disconnect =	evdev_disconnect,
729 	.fops =		&evdev_fops,
730 	.minor =	EVDEV_MINOR_BASE,
731 	.name =		"evdev",
732 	.id_table =	evdev_ids,
733 };
734 
735 static int __init evdev_init(void)
736 {
737 	input_register_handler(&evdev_handler);
738 	return 0;
739 }
740 
741 static void __exit evdev_exit(void)
742 {
743 	input_unregister_handler(&evdev_handler);
744 }
745 
746 module_init(evdev_init);
747 module_exit(evdev_exit);
748 
749 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
750 MODULE_DESCRIPTION("Input driver event char devices");
751 MODULE_LICENSE("GPL");
752